Specifications:Sigma 20mm f1.8 EX DG Aspherical RF is one of several EX Series lenses. It is the first 20mm Super wide-angle lens in the world with a large aperture of F1.8 and angle of view 94.5°. It has Macro focusing capability with a minimum focusing distance of 20cm/7.9inches (reproduction ratio 1:4). The iris diaphragm has 9 diaphragm blades to obtain beautiful out of focus image. It incorporates an aspherical lens element in the front as well as rear lens groups, to minimize distortion, spherical aberration and astigmatism. The lens has non-vignetting optical construction, in order to obtain adequate peripheral brightness with open aperture. This is especially desirable for digital cameras. The lens incorporates a rear focus system eliminating front lens rotation, thus allowing the use of a Perfect Hood and easy use of polarizing filters. The lens also incorporates dual-focus mechanism. It is easy to hold the lens, since the focusing ring does not rotate during auto-focus, yet it provides adequate focusing torque of the focusing ring during manual focusing of the lens. The lens materials used in this new lens are lead and arsenic free ecological glass.

This was my first real wide angle. I owned this lens for about two years, and many of my favorite shots were made with this lens. The build quality is fantastic, I would compare it to some of the L series lenses in build quality and weight (so it is a little on the heavy side). The autofocus isn't real fast, but it's not bad either. This focal legnth isn't really intended for tracking fast moving subjects anyway. I always found the image quality to be good, often times I was really quite impressed. The color rendition was always spot on too.

I have no complaints about this lens at all, I would suggest it to anyone looking for a fairly wide fast prime for a crop body.

Jul 21, 2012

markshelbyOfflineImage Upload: Off

Registered: Sep 28, 2005Location: United StatesPosts: 672

Review Date: May 21, 2012

Recommend? yes |
Price paid: $400.00
| Rating: 8

Pros:

Good value for money; fast

Cons:

focus is noisy and slow, and switching between auto and manual is a hassle.

If you want a fast wide angle lens and you don't want to spend $1500 then this lens is it. The autofocus is noisy and slow, and to switch between manual and autofocus you have to remember to push/pull the focus ring (which btw is prone to accidental pushes/pulls) as well as the normal on/off switch. And it's not my sharpest lens.

If I had the money I'd get the Canon 24mm f/1.4. But this lens gets the job done for a third the price, it's reasonably sharp and is pretty solid.

May 21, 2012

OskarOfflineImage Upload: Off

Registered: Mar 16, 2012Location: AustraliaPosts: 0

Review Date: Mar 16, 2012

Recommend? yes |
Price paid: Not Indicated
| Rating: 8

Pros:

Very good lens , I use it mainly for arcectichal projects for certain work where there is not time for the tilt shift set up, it , and for underwater work on a NIkon D3 in an Aquatica housing , I had one of the first production models and it reliable sturdy but has some drawbacks.but with a d3 at full iso and lens at full open you can shoot in a dark room and get an image .
At F16 landscapes are spot on , I use it on a D3X and that's where this lens shines and have award winning shots from it .

Cons:

Wide open sharpness is touch and go and I just can not get a sharp shot so shooting 5.6 up is pretty good.

In a nutshell at f 16 up sharp as a tack , wide open not good
Put it on a D3x and it's a killer lens 20 mm is just righ for a cropped landscape to a panoramic format, for my jobs where I never know what to expect it is always in my kit.

Mar 16, 2012

jessi74OfflineImage Upload: Off

Registered: Aug 22, 2008Location: United StatesPosts: 3

Review Date: Nov 5, 2011

Recommend? yes |
Price paid: $400.00
| Rating: 5

Pros:

Wide and fast.

Cons:

Wasn't sharp on DX. Giant 82mm filter. Getting pretty big. It went back to the store. Awkward MF clutch.

Nov 5, 2011

flowatrack2002OfflineImage Upload: Off

Registered: Feb 12, 2011Location: IrelandPosts: 0

Review Date: Feb 12, 2011

Recommend? yes |
Price paid: $150.00
| Rating: 9

Pros:

sharp, fast AF, build quality is good

Cons:

flare, loud AF

I really like this lens, very good for landscapes, soft at f1.8 but sharp from f2.8 and it's excellent from f4.5 , at f5.6 has the same sharpness as the Sigma 10-20mm DC f4.5-5.6 at f9 so you can imagine how good is this lens. Little flare and CA but if you don't shoot right into the sun then you won't see it.
Overall a quality lens for a small price.

Feb 12, 2011

nycandreOfflineImage Upload: Off

Registered: Apr 23, 2009Location: United StatesPosts: 22

Review Date: Sep 22, 2010

Recommend? |
Price paid: Not Indicated

Pros:

Affordable, great quality glass and great quality images, large aperture, focuses well, not so heavy or obtrusive

Cons:

Not all that sharp in the corners, not so great bokeh wide open, does flare

A little gem of a lens. Most reviews do pan it, and I noticed that none of the pros highlighted in Sigma's own gallery have any shot with it. They seem to like the 10-20 and 70-200. Maybe they suffer from the 'sharpness syndrome' malady. As for me, I find that it is sharp enough in the centre, does have issues with bokeh wide open, and flare in extreme situations - but then it focuses fast enough on my D700, is maneuverable and not that heavy, and most important gets the shot.

Great for macros. But really busy bokeh, at least when shot at f2/0, an extreme case - Note the flower is very close, maybe a few inches - its diameter is about the size of two quartershttp://www.flickr.com/photos/nycandre/5016914598/
Exif: f/2.0 1/2500 ISO 800

It does flare when shot right into the sun - Notice the cool small green sphere, totally an artifact of the lens. You probably won't get that with a Zeiss. Then again I sort of like that imperfect personalityhttp://www.flickr.com/photos/nycandre/5016270909/
Exif: 1/640 f/5.6 ISO 800

Getting back to basics - it gets the shot !
Impromptu grab shot, barely had time to shoot from the hip, letting the autofocus work its thing. I'd say it did a great job - getting the shot is what it's all about in the end. And I 'd say it is plenty sharp enough.

bokeh wide open is busy some flare in certain cases tho not sure how it stacks up against other lenses (like Canon/ Nikon/ Zeiss )

I don't get the negative reviews. Started shooting it and it is very sharp at least in the center area even wide open.
Rarely bothers me since I don't usually care for the borders being sharp anyway, but I can see how it could bother landscape photographers.

It took awhile but I finally found a great copy of this lens. Its wide open sharpness rivals my 135L and 85L easily...which I never thought would be possible from a sigma lens. Great Buy!

Apr 25, 2010

CarusoPhotoOfflineImage Upload: Off

Registered: Nov 30, 2006Location: United StatesPosts: 54

Review Date: Aug 18, 2009

Recommend? yes |
Price paid: Not Indicated
| Rating: 10

Pros:

focal length; wide aperture; build quality; sharpness; "fun" quotient

Cons:

big for a prime (though this may bother some, it doesn't necessarily bother me)

I’ve grown very attached to the Sigma 20mm f/1.8. I held off a long time buying one because of the widely mixed reviews. However, the appeal of a 20mm prime that opens up to f/1.8 eventually wore down my resistance. Now that I own it, I am hooked.

I’m not a pixel peeper, but I do know when I like a lens or don’t like a lens. At various points I’ve had the Canon 24mm f/2.8 and the Canon 28mm f/2.8. From the first few photos I shot with each of them, I just knew I was going to be returning them--and, in fact, I did. They both went back. I’d heard great things about each lens, but I just felt that the performance from each of them simply didn’t make up for the fact that they only opend up to f/2.8. I compared the photos from these lenses to photos made with my f/2.8 zooms, and the zooms won each time.

With this baby, though, I get a nice, wide lens with a big aperture…and I like the photos I get from it. I find that my "keeper" ratio is higher with this lens than most others I own, save the 135 f/2L and the 85 f/1.8.

Perhaps I got lucky and got a “good” version of the lens right off the bat. All I know is that it is another prime lens that is spending a whole bunch of time in my bag.

Aug 18, 2009

dennisvillegasOfflineImage Upload: Off

Registered: Jan 21, 2008Location: PhilippinesPosts: 0

Review Date: Nov 6, 2008

Recommend? yes |
Price paid: Not Indicated
| Rating: 10

Pros:

Wow...wow! i never knew Sigma could be this good! This is cheap, rocking 1.8!, and can work in full-frame dslrs! I love the colors, the bokeh, the sharpness, and the build quality.
Great lens, a great bargain, too!

Cons:

None maybe should have HSM even if I have to pay a 100 dollars more.

Superior lens, one of Sigma's underrated lens...Even works better if you work it with a full-frame such as the 5D or the D3.

I am very satisfied and will not hesitate to buy again.. Some rich hard to please fellows do not like it and would like to trash hundreds of dollars buying more expensive though not better lenses.

Nov 6, 2008

Gi11iesOfflineImage Upload: Off

Registered: Oct 3, 2008Location: United KingdomPosts: 20

Review Date: Oct 5, 2008

Recommend? yes |
Price paid: Not Indicated
| Rating: 9

Pros:

Sharp, cheap, has variety of uses, works fine on 5D

Cons:

Can be noisey, Sigma Clutch System

One of my favourite lenses, works great on both 20D and 5D. Extremely sharp at F4 and above. I prefer the results from this lens for landscapes above my 17-40 L.

In low light situations without flash it is OK but not great, but gets acceptable results .... and can get shots otherwise you would not get with other lenses.

F1.8 to F2.8 - OK, F2.8 to F4 - Pretty Good, F4 + Very Good.

The Sigma Clutch System is a pest, and it can be pretty noisey if hunting for focus.

All in all, for the money I am not complaining, and highly recommend.

Oct 5, 2008

jmspearsOfflineBuy and Sell: On

Registered: Aug 10, 2006Location: United StatesPosts: 244

Review Date: Feb 10, 2008

Recommend? yes |
Price paid: $300.00
| Rating: 9

Pros:

Wide on a 5D!!!

Cons:

Soft at corners.

Well worth the price!!!! I love the low light uses for this lens!

Feb 10, 2008

Mark LijesenOfflineImage Upload: Off

Registered: Oct 10, 2007Location: NetherlandsPosts: 56

Review Date: Oct 10, 2007

Recommend? yes |
Price paid: Not Indicated
| Rating: 9

Pros:

sharp images, build quality,

Cons:

filter size, colors are slightly off

Picked up this lense second hand from a photgrapher I know. I wasn't too happy with the reviews I read on Canon's wide non-L primes, so I gave Sigma a shot.

I am pretty pleased with this lense and use it for group portraits and landscapes on my 300D. It's quite sharp @1.8 and sharp @2.8. I think that's not too bad for a wide lense (actually, Canon's 20 mm only starts @2.8). Build quality is fine, as to be expected on a Sigma EX. Some people complain about the AF/MF-switch. I can imagine why, but I got used to it within a week and it never bothered me since.

The close focus distance allows for fun perspective distortion pics.

As I like to shoot landscapes with a polarizing filter, I was not too pleased with the 82 mm filter size, and like most Sigma lenses, it gives a slightly yellowish result. Nothing that can't be fixed in postprocessing though.

Oct 10, 2007

simon_saysOfflineImage Upload: Off

Registered: May 22, 2006Location: CanadaPosts: 812

Review Date: Sep 16, 2007

Recommend? yes |
Price paid: Not Indicated
| Rating: 7

Pros:

Currently the only 20mm lens with a fast f/1.8 aperture - images are very usable at f/1.8, especially for small prints. It is full-frame compatible. Lens is well built and solid. Lens length does not change during focusing. The minimum focus distance is very close! That allows for some very dramatic shots. Wide aperture + close focusing = thin DOF! Amazing to get background blur with a wide angle lens!

Cons:

The lens is a bit soft at f/1.8, though not too bad (but that should be expected, considering the focal length and price). The focusing motor is quite loud. Too bad it doesn't have HSM (and hence no manual focus override). The 'clutch/switch' system for focus selection is clumsy (to switch between AF/MF there are two steps needed - very inconvenient). The lens also uses 82mm filters, so not too common.

I picked up this lens after reading various things about it. There are many complaints about it being soft at f/1.8, etc. However, considering that it is a full-frame wide angle lens with a large f/1.8 aperture, I think it's hard to complain about it, given it's price point. At wide open aperture, I found the images to be acceptable for smaller sized prints.

The lens had a nice solid and weighty feel to it. It has a nice large focus ring, but the AF/MF switching mechanism is very dumb: you need to shift the ring position AND set the focus switch before being able to change focus modes - how annoying! (This lens would be much better with HSM). The focus motor is also a bit buzzy.

Surprisingly, I found this lens to be a lot of fun to use. Unusually, I ended up using this lens for close-up shots more than wide-angle shooting. The minimum focusing distance on this lens is crazy! You can literally get right into-the-face of the subject you're shooting. With a wide angle focal length and a wide aperture, you can get some cool looking close-up shots - and you get dramatic background blur too!

Sharpness isn't everything - this lens lets you get certain shots that you can't get otherwise. E.g. low light wide angle shots, close-up wide angle shots, etc. Maybe not the best for landscape, but otherwise it's still a very unique lens.

Sep 16, 2007

twoshadowsOfflineImage Upload: Off

Registered: Jul 10, 2006Location: United StatesPosts: 1417

Review Date: Jul 24, 2007

Recommend? yes |
Price paid: $410.00
| Rating: 9

Pros:

useable f/1.8, insanely sharp by f/5.6, FF compatible, solid build

Cons:

No way to grip lens without constantly switching focus mechanism

This lens is good at what it does. It is the only 20mm f/1.8 lens for dslr's on the market. Surprisingly, this lens ranks among my sharpest (135L, Sigma 180mm macro, 300mm f/4 L IS, 85 f/1.8) and is freakishly sharp at f/5.6. It is a good landscape lens and I use it for hdr's and panoramas as well. Also good for band pics in tight quarters.